My GVWR & GCWR <is this right>

bushpilot · 09-21-2011, 04:31 PM

as being discuss in another thread -
theres some question as to my weight rating/capability....

does seem low ? for a single screw (42ft) FL Columbia ?
Ive got the MBE4000 (benz/detroit 450hp) w/ the 12speed auto (Meritor/ZF).

the below leads me to believe that im only "permitted" 5799 lbs (after water/propane/fuel) including trailer etc.

Ive weighed the truck fairly well loaded (grill, chairs, tools, blocks of wood for the jacks/stablizers, some food and clothing & 1/2 a tank of water) and the scale tipped a knats eyelash over 30k lbs. - which I take it to mean i could add another 10k lbs of stuff (trailer/clothing/ice etc).

Quote:

so the GVWR (13880+22700) is 36580 (which i think i said before)

im going by what the drivers door tag & the tag inside the kitchen cabinet says combined (loaded coach and trailer) is 40k.

i WISH i was 80k rated (im single screw-ed) - ive got no plans to pull a stacker <mental note: play the lotto>....but if im not careful i could be OVER weight - pulling a simple little jeep (ill just leave that topic alone).

hot rod · 09-22-2011, 11:30 AM

That CCC sticker is a bunch of legalese that the government makes the coach mfg. calculate based on the gvw of the coach by itself (36580 based on adding axle ratings together) minus what the government THINKS it will weigh when fully loaded with normal things like water and people, hence the silly formulas like "5 persons @ 154# per person" (apparently the d.o.t. does not read the papers about how fat Americans are these days. lol.). So by their fantasy land calculations, after you have your tanks full and 4 of your best friends loaded in, you can load an additional 5799# in the COACH. Where you'd put it I have no idea, but the govt. says you can!

That 5799# is just a made up number for the coach and has nothing to do with the weight of the trailer you can pull. That is a little more real world discussion. The coach builder (not Freightliner) has assigned your truck a GCWR (max truck and trailer combined) of 40,000#. This means that the TOTAL of both cannot exceed 40,000. So using Uncle Sam's numbers from your CCC tag, your coach should weigh 30781# with full tanks and 4 of your best friends, leaving a difference of 9219# for your trailer towing capacity in theory. Of course if you also bring your dog, then the trailer weight goes down, so Fido may have to stay home. You get the idea. Oh yeah, and keep in mind that you still cannot exceed the max rating of EACH axle, even if your total is under 40000. But that should not be a problem, most of trailer weight should be on it's own axles and only a small amount on the hitch.

So you are correct based on your actual scale weight that you can pull almost a 10000# trailer. And Bobz is sort of correct, your drivetrain should be able to handle 80000#, but being single screw it would never have that high of a GVWR anyway, regardless of what rating the coach builder slaps on there. It would have to be a twin screw to have a GCWR that high.

To be honest at this point my knowledge runs out. I am not really sure where they dream up the GCWR number from. I do not know if it is an arbitrary number created by the coach builder (as opposed to Freightliner). Am I correct that there is no GCWR on the Freightliner tag on the door? Just a GVWR? If not apparently the coach builder can create the GCWR at a number above the GVWR (for just the truck) figure. I wish I knew how they calculate that. Maybe based on the max rating of the hitch they install? Or some other arcane government math? Input from other posters would be appreciated on that detail.

I have a similar dilemma on my own project. I am building a toter project to pull my 5th wheel / gooseneck trailer to replace my dually. Like yours, it has only GVWR ratings on the door tag, and no GCWR at all. My GMC 5500 Topkick chassis was a box truck originally, and rated at 25950#. It never had a hitch before I got it, so apparently no GCWR rating. Now, at 25990#, and using the math above, it would actually be able to pull less trailer in theory than my dually, which is just crazy. So I am guessing that the coach builder (me) can rate the GCWR higher like on your unit? I am going to have to or I am toast at the first scalehouse that bothers me. Once again, any input out there on how that GCWR is arrived at would be appreciated.

bushpilot · 09-22-2011, 12:16 PM

I appreciate the input and opinions...im just a bit surprised (who isnt) at the weight and the "suggested" combined capacity....at the end of the day its more than enough for us - itll haul the trailer & car or motorcycles we have <safely>.

The 90lb sheep dog goes - even if i have to leave my beer or whiskey at home

Ill look again but i dont think there is a GCWR from FL on the drivers door.

I agree - id dont for the life of me know how id get 5700 lbs of stuff IN the coach...gold bars maybe ??

Bob86ZZ4 · 09-22-2011, 11:41 PM

My truck is pretty close to your's, Don. I often pull a 24' enclosed car trailer. Fully loaded we figure the trailer is about 8k lbs. We've never weighed the trailer. There is absolutely no way to tell the trailer is there from the driver's seat without looking in the mirrors or backup camera. The truck simply is not affected one bit by the trailer. My hitch is rated by United Specialties (the coach builder) at 40k lbs. I can't for the life of me figure how Haulmark could say you could only pull a 5k lb. trailer with that truck. I've got to take pictures of my weight stickers when I get to my truck because I wonder what I'm restricted to for gcvw. I don't remember looking for or seeing that rating. I just know my axle ratings.

Hotrod, why would the number of axles matter for the trailer weight? If say my rear axle is rated at 22,700 lbs. And with no trailer attached the rear axle scales at 16k lbs. Wouldn't that mean I could put a trailer on that has a tongue weight something like 6k lbs? Obviously that's probably too much tongue weight since the tongue should be 10% of total trailer weight, shouldn't it? So, if my hitch is rated at 40k lbs I should be able to put a 40k lb. trailer on that would only have a 4k lb. tongue? Maybe I'm totally wrong here? I can't get to my camper for about a week to check the door stickers. At least now I'm subscribed to this thread.

bushpilot · 09-23-2011, 02:37 AM

Bob Thanks ! at the end of the day ive got more truck than i need...and THAT is the way we wanted it...in our mind CONVERSIONS are safer, more capable coaches <period> !

bob - whats your front axle ? is it the 12.880 like ours ?

its encouraging that you pull that trailer <safely> w/ your set up - should be a walk in the park for mine too....if you get to the houston area ive got a 50 amp connection and hose w/ your name on it (cold beer too) !

hot rod · 09-23-2011, 01:50 PM

OK, my head is starting to hurt.

Bobz, I may have to stand corrected on the single vs. twin screw, at least partially. While it may be technically possible to scale 80,000 with a single screw tractor and a triple axle trailer, I doubt it's gonna happen in the real world. Here is a link to the dot "bridge rule" that sets max federal weights for the highway:

Bridge Formula Weights- FHWA Freight Management and Operations

A single axle can be max 20,000#, tandems can be 34,000#, and triple axles can be 42,000#. So if you have a triple axle trailer maxed out at 42000 and perfectly balanced so your drive axle hits 20000, that leaves you 18000 you have to get onto the front axle somehow to add up to 80000. In the real world you'll never see a combination unit anywhere close to 80,000# without a twin screw truck.

Anyway, like I said my head is starting to hurt. So it seems that even though some of your trucks may have an axle rating of over 20,000#, you are still limited to 20,000# max per axle by federal weight rules. So you can spec out as heavy an axle as you want, but you can still only be at 20,000 per axle on the highway.

I know, I know, "but officer, it's an RV" not a truck. If you're toting that racecar trailer more and more states are cracking down on those of us that have been skating, they need money and the theory is if you are racing, you are racing for a payout and it is therefore a business and your rig is commercial regardless of what the license plate says, and they will enforce full dot regs just like a semi. So it's just a matter of time until we are crossing scales, unless you are truly just an RV. But let's face it, almost everyone with a truck conversion vs. a traditional RV has it to have the ability to haul a heavy trailer and/or skate on the dot stuff. Check out some of the racer horror stories on the old hippie forum.

Bob86ZZ4 · 09-29-2011, 02:28 PM

I bet it's not that uncommon for a single screw tractor to run 80k lbs. total. There's tons of Fedex and UPS ones running doubles and triples all the time. I find it hard to believe they're only running 40k lbs. total like Don's truck is rated (incorrectly I think).

SHORTS · 09-30-2011, 10:52 AM

As I read this thread it appears that their is some confusion about weight rating and towing capacity and combined gross weight. I interpret the axle weight to be just like it sounds, max allowed weight for each axle, steer,drive/drives and trailer. the coach can weigh up to the max combined weight capacity of the axles including coach with load and trailer tongue weight, in this case 36580. What ever trailer that you tow should not exceed it,s rated capacity less the tongue weight that is carried by and included in the trucks gross weight. Put the beer in the trailer and keep the dog up front in the copilots seat.

Bob86ZZ4 · 09-30-2011, 05:18 PM

Yes Shorts, I am confused. But it's the most common state of mind for me so I'm comfortable with that. Isn't GCWR the max weight of the whole thing, trailer and truck and everything? In Don's picture above it looks like they say GCWR is 40,000. That's just crazy sounding to me that they say he can only pull about a 3500 lb trailer if he loaded the truck to it's max. I just checked out the door stickers on my truck today. I'll post some pictures. I can't find the GCWR anywhere. I wonder what that means?

bushpilot · 09-30-2011, 06:22 PM

Bob - i dont have a GCWR on my door sticker either.
Do you have a GCWR on your coach label (mine is on the door under the sink).

Just watch that show (american trucker - stupid as it can be)....they were showing tractors w/ 140+ inch sleepers - pulling enclosed car haulers, im guessing those guys are close to 80k.

SHORTS · 09-30-2011, 08:28 PM

Bob, I'm glad that you are comfortable with confused, I've been told that I'm both hopeless and beyond help.
My understanding/interpretation is that the GAWR (gross axle weight ratings) as determined and specified by both the component and truck manufacturer are added together to determine the GVWR (gross vehicle weight rating) as specified by the chassis manufacturer The GVWR is the stated max safe operating weight of the chassis, if you overload the chassis the assembly is legally being abused and all bets are off as far as the manufacter and lawyers are concerned.
Consider any towed item to be a seperate vehicle/component that has it,s own GAWR plus the tongue weight that are added to determine the GVWR .
When you hook a trailer to the truck chassis only the tongue weight of the trailer becomes part of the truck chassis' gross weight.
The GCWR (gross combined weight raring) is the combined total of all of the axle capacities that the rig can weigh without overloading or abusing the package as determined by the component manufacturers.
The powers that title and license vehicles determine how much weight you can legally carry by their own formulas, usually pounds per inch of tire width, they will write what ever weight rating that you want to pay for as long as it doesn't exceed the manufacturers stated capacities. trailers are usually titled/licensed by weight determined by a certified weigh ticket. Just don't get caught overweight at the scales if you're a commercial vehicle.
Since RV's are not commercial vehicles they don't have to scale and draw very minimal attention from the weighmaster.
With all of that being said if a LEO wants to be difficult they could probably find a reason to weigh you and it is only prudent to comply with the GCWR and within 10% overweight on any given axle

Bob86ZZ4 · 10-01-2011, 10:43 AM

Don (Bushpilot), I can't find any such label or sticker showing GCWR.

Okay Shorts. So I'm getting closer. Let's keep working on this though. Don's sticker shows GCWR of 40,000. Doesn't that seem odd to you that he could only pull about a 3500 lb. trailer with his truck? Our trucks are fairly close in size and weight. I pull a 8k lb. trailer and can't even tell it's there. I'm wondering why I can't find anything showing my GCWR?

SHORTS · 10-01-2011, 09:35 PM

I'll bet a dollar for a donut that the 40,000 gross combined weight sticker was generated by the coach builder,not the chassis manufacturer and it only allows for some type of lightweight class 2 hitch assembly that was installed on the bumper almost as an afterthought instead of a quality hitch assembly that is securly tied into the chassis and engineered to handle 30 or 40,00 pounds gross with a 3500 pound or more tongue weight like we see installed on toters.

SHORTS · 10-02-2011, 11:02 AM

another way to look at this, 36580 axle capacity +10% = approximately 40k gross combined weight of the chassis, coach and load. It's probably time to call the people that installed the coach and ask them how they figured the GCWR

bushpilot · 10-02-2011, 09:39 PM

clearly the label was installed and "calculated" by the coach builder (haulmark)....freightliner had NO idea our chassis might have a 210g water tank much less all the other crap it has.

our hitch is tied to the frame - w/ SUBSTANTIAL plate steel - its no "bumper" hitch much less an "after thought"

ive NEVER seen air line connections on a class 2/bumper hitch....ive got a class 5 on my f350 and my coach hitch makes that look like child's play !

SHORTS · 10-02-2011, 09:55 PM

Ok, after seeing the hitch, I'd go with the GCVW of 40k for the coach including the tongue weight of your trailer of choice. with a federal weight limit of 80k that means a trailer capacity of 40k plus the 10%tongue weight on the truck.GCVW of the trailer and load. All of this is based on the assumption that the hitch and trailer axle capacities are not being exceeded.

#90-GTSC · 10-03-2011, 08:07 PM

I'll bet that square light provides more than enough illumination when hooking up or unhooking at night. Nice touch!

bushpilot · 10-03-2011, 08:18 PM

Quote:

Originally Posted by #90-GTSC

I'll bet that square light provides more than enough illumination when hooking up or unhooking at night. Nice touch!

thats not a light, thats a back up camera - it gives me a visual of the hitch, trailer tongue and ball when connecting and towing....the backup camera has infrared LED's to illuminating its "view" even in TOTAL darkness.

that camera wasnt originally in that location - i moved it there in an emergency after i had a wiring failure in its original location (at the top of the coach).

I have since repaired the wiring and installed a better camera up top...so now i have TWO rear facing cameras w/ different perspective (one low for viewing the hitch) and one high (for viewing the trailer(s) and traffic).

Bob86ZZ4 · 10-07-2011, 06:29 PM

So Don (Bushpilot), have you called Haulmark and asked to speak to somebody in customer support? Then ask that person how come that sticker says you can only pull a 3500 lb. trailer. I'd love to hear their response.

Don Mcl · 10-07-2011, 11:35 PM

my sticker which is also on the kitchen cabinet door.

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